SPECIES FACT SHEET
Common Name: Heidemann’s damsel bug
Scientific Name: Hoplistoscelis heidemanni (Reuter, 1908)
Phylum: Mandibulata
Class: Insecta
Order: Hemiptera
Family: Nabidae
Subfamily: Nabinae
Taxonomic Note:
This species was originally placed in the genus Reduviolus, then moved to
Nabis, and finally moved to Hoplistoscelis by Henry & Lattin (1988).
Conservation Status:
Global Status (2001): G4
National Status (United States): NNR
State/Province Statuses: Oregon (S2), British Columbia (S1)
(NatureServe 2013).
Technical Description:
Hoplistoscelis heidemanni is a small (6-8 mm), brown, damsel bug with
distinctly long, thin antennae (Applegarth 1995). The damsel bugs (family
Nabidae) are a small group of important generalist predators frequently used in
biological control programs (Kerzhner & Henry 2008). Like other heteropterans,
the mouthparts are of a unique piercing-sucking type, and the basal portion of
the front wing is thickened and leathery, while the apical portion is
membranous. Members of this family are mostly dull-brownish, occurring in
both short-winged (micropterous) and long-winged (macropterous) forms (Maw
et al. 2000). In North America, this family is distinct from other true bugs by
the front femora being enlarged (swollen), and the membrane of the hemelytra
(when developed) having number of small cells around the margin (Triplehorn
& Johnson 2005, Arnett 2000). This family is further described as follows (Maw
et al. 2000):
Ocelli are present; the labium is four-segmented. The fore legs have a
dense pad of hairs (fossula spongiosa) at the distal end of the tibia. The
costal fracture of the hemelytra may be present or absent. The
membrane of the hemelytra has two or three elongate cells, and usually
has emanating veins and a stub. The abdomen has three dorsal scent
gland openings between terga 4/5, 5/6, and 6/7. The male genitalia are
usually symmetrical (Maw et al. 2000).
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The Nabidae family contains two subfamilies, 11 genera, and 39 species in
North American (Kerzhner & Henry 2008, Henry 2009). The Hoplistoscelis
genus belongs to the Nabinae subfamily. The following characters distinguish
the Hoplistoscelis genus from other closely related genera in the subfamily:
head behind the eyes parallel-sided or nearly so (as opposed to obliquely
narrowed behind the eyes); body mostly grey or brownish in color (as opposed
to shiny black with yellow appendages) (Harris 1928). Adults of this genus are
usually wingless or have small rounded pads instead of functional wings. They
are about 6-8 mm long, and their bodies are generally wider than the other
damsel bug genera (Slater & Baranowski 1978, Elvin & Sloderback 1984,
Applegarth 1995).
A total of five species of Hoplistoscelis occur in North America north of Mexico:
H. confusa, H. heidemanni, H. hubbelli, H. pallescens, and H. sericans (Kerzhner
& Henry 2008). With the exception of H. confusa in the southwestern United
States (e.g., Arizona, where both species have been documented), none of these
species are known to overlap with H. heidemanni in range. In Oregon and
Washington, Hoplistoscelis heidemanni is the only member of this genus known
to occur. Morphologically, Hoplistoscelis heidmanni is distinguished from other
members of the genus by the following characters: front and mid femora
armed beneath with minute short, rather blunt, blackish teeth (as opposed to
unarmed or with minute spine like setae, never short teeth); tibiae annulate
throughout their entire length (as opposed to not annulate, or if so, only at the
base and apex) (Harris 1928).
A full description of the species is as follows (Harris 1928):
Oblong or oblong-ovate, fuscous to fusco-testaceous, opaque, pubescent,
also thickly pilose. Head about as broad as long, with two posteriorly
converging fuscous lines above. Eyes large, the length of one equal to
width of vertex. Ocelli placed closer to eyes than to each other. Antennae
long, testaceous, segment I at base and II before the apex with fuscous
rings; segment I equal to width of head through eyes. Rostrom with
segments II and III subequal, each slightly longer than antennal segment
I. Pronotum with a distinct median longitudinal line and more or less
distinct pattern on anterior lobe, and five obscure lines on posterior lobe
fuscous. Scutellum with a calloused white spot on each side. Hemelytra
with moderately long, semierect pubescence, somewhat irregularly
spotted with brownish fuscous, the veins lighter and often tending
toward crimson. Legs clothed with prominent erect or semierect hairs,
fusco-maculate, the tibiae distinctly annulate. Front and mid femora
armed beneath with distinct short grain-like teeth, the former about 3.5
times as long as thick. Hind tibia with its longer hairs about twice as
long as the diameter of the tibia and standing out almost
perpendicularly. Abdomen above densely clothed with prostrate, silvery,
downy pubescence; with a distinct naked patch at the base of each
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tergite in the median line, also each tergite on either side with a
transverse naked patch. Connexivum testaceous sometimes obscurely
marked with crimson, the segments each with a basal fuscous patch.
Venter with a broad stripe on each side and a narrow median one
fuscous, each segment with a conscious naked patch on either side next
to the connexivum. Male narrow, rather elongate, the clasper slender
with a long blade. Brachypterous form: pronotum as broad as long, the
anterior lobe rather strongly arched. Hemelytra extending onto the base
of third dorsal segment, broadly rounded or almost truncate at apex;
membrane very small, without veins. Length 7.2-8.7 mm, width 1.561.92 mm (at abdomen, 2.7-3.6 mm). Macropterous form (female):
pronotum distinctly broader than long. Scutellum much larger than in
brachyperous form. Hemelytra extending scarcely to tip of abdomen,
obliquely narrowed from a point opposite middle of commissure;
membrane with veins fuscous, broad and prominent. Length 8.88 mm;
width 2.28 mm (at abdomen 3.5 mm).
Harris (1928) describes this as a distinct, easily recognizable species.
See Attachment 4 in the Appendix for a photograph of the brachypterous adult
female. A photograph of the macropterous adult is available on BugGuide.net
(http://bugguide.net/node/view/296746#631950, accessed March 2013).
Immature: Immature nabids have a long, slender, 4 segmented labium arising
from the anterior part of the head (Elvin & Sloderback 1984). They also have
long, slender antennae, apical tarsal claws, and usually 3-4 pairs of scent
glands present on the abdomen. The labium is not located in a rostral groove in
the gular region (Elvin & Sloderback 1984). The nymphal instar of a particular
immature nabid can be determined by assessing the amount of wing pad
development (see Elvin & Sloderback 1984 for details). Some immatures of
Hoplistoscelis show little or no wing pad development; however, they can be
distinguished from immatures of the other genera by their distinctive body
shape (pear-shaped as opposed to elongate-oval) (Elvin & Sloderback 1984).
There are no keys available for identifying the nymphs to species, but note that
H. heidemanni is the only member of this genus known to occur in the Pacific
Northwest. See Attachment 4 in the Appendix for an illustration of a
representative nymph of this genus.
Life History:
Nabid bugs are aggressive generalist predators, feeding on wide variety of small
arthropods including caterpillars, aphids, and plant bugs (Marshall 2006,
Triplehorn & Johnson 2005). Nabid nymphs are active shortly after hatching
and begin feeding immediately, often on prey considerably larger than
themselves (Lattin 1989).
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The phenology of this species is poorly known. According to Applegarth (1995),
specimens have been found [presumably in Oregon] in early spring and late
summer, although both of the recently recovered Oregon specimens were
collected in August (OSAC 2013). This species has been collected in June &
October in California (BugGuide 2013, OSAC 2013), July and October in Idaho,
and July in Arizona (OSAC 2013).
Nabids tend to overwinter as adults (Applegarth 1995, Lattin 1989). Adults of
Hoplistoscelis sericans have been found overwintering in harvested corn fields
in Florida; in this study, 10 adults were found between the layered husks
around shelled cobs, and two adults were collected under the corn leaf sheath
(Plagens & Whitcomb 1986).
Dispersal behavior in H. heidmanni has not been examined. The macropterous
(fully-winged, flight capable) form of some adult nabids are known to move
considerable distances (Lattin 1989), probably in response to instable habitats
or food sources.
Many aspects of this species biology are unknown, including dietary
preferences, mating behavior, oviposition site selection, number of eggs laid,
development time, life span, number of generations per year, dispersal
behavior, and overwintering behavior and habitat.
Range, Distribution, and Abundance:
This species is known only from Western North America. In Canada, it is
documented from British Columbia (Anarchist Mountain and Haynes
Ecological Reserve-Osoyoos) (Scudder 1996, Maw et al. 2000). In the United
States, it is documented from Idaho (Latah County), California (Monterey
County), Oregon, Arizona (Yavapai County), and Utah (Henry & Lattin 1988,
Applegarth 1995, OSAC 2013, USNM 2013, Kerzhner & Henry 2008).
In Oregon, known records are from Benton County (Corvallis) and Curry
County (Humbug Mountain) (Applegarth 1995, OSAC 2013).
BLM/Forest Service lands: This species is Suspected on Siuslaw National
Forest and BLM land in the Coos Bay District, based on proximity to a known
record. The Eugene and Salem BLM Districts also suspect the species.
Abundance: Abundance estimates of this species have not been conducted.
Known collections in Oregon are both of single individuals (OSAC 2013).
Habitat Associations:
Applegarth (1995) describes the habitat for Hoplistoscelis heidemanni as forest
riparian areas and skunk cabbage (Lysichiton americanus) swales. The habitat
at the Humbug Mountain site was described as a stream bank (Applegarth
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1995). The habitat at the Corvallis site is unknown. In Idaho, this species has
been collected from “yellow pine”, and in Arizona, from Ceanothus, a genus of
shrubs in the family Rhamnaceae (OSAC 2013).
In Eastern North America, the related H. sericans has been found under bark
of a dead tree (BugGuide 2013). The related H. pallescens has been found
visiting flowers, under leaf litter in a flower bed, on the top surface of leaves,
and preying on adult flies (BugGuide 2013). Both H. pallescens and H. sericans
have been found at lights (BugGuide 2013).
Threats:
Threats to this species have not been evaluated. Habitat loss or alterations are
probably primary threats, but specific issues are difficult to assess given the
limited information on this species’ distribution and habitat requirements in
Oregon.
Conservation Considerations:
Inventory: This species is known from very few collections in Oregon, perhaps
due to limited sampling effort. Further surveys are needed for this species in
Oregon, and will be critical in evaluating its current status and habitat use in
the region. Initial surveys are recommended on BLM and Forest Service land in
the vicinity of the known Humbug Mountain site where this species was last
collected 1965. In British Columbia, this species is also considered a priority
for inventory and descriptive research, due to being very rare or endangered at
both the provincial and national levels (Scudder 1996).
Management: Protect all known and potential sites from practices that would
adversely affect this species or its habitat.
Research: Many aspects of this species’ biology are in need of study including
food preferences, mating behavior, oviposition site selection, number of eggs
laid, development time, life span, number of generations per year, and
overwintering behavior.
Prepared by: Sarah Foltz Jordan, Xerces Society for Invertebrate Conservation
Date: 8 April 2013
Edited by: Sarina Jepsen, Xerces Society for Invertebrate Conservation
Date: 10 April 2013
Final edits by: Rob Huff, Conservation Planning Coordinator, FS/BLM
Date: 22 April 2013
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ATTACHMENTS:
(1)
References
(2)
List of pertinent or knowledgeable contacts
(3)
Maps of known records in Oregon
(4)
Photograph of this species & illustration of relative
(5)
Survey protocol for this species
ATTACHMENT 1:
References.
Applegarth, J.S. 1995. Invertebrates of special status or special concern in the
Eugene district. U.S. Department of the Interior, Bureau of Land Management.
126 pp.
Arnett, R.H., Jr. 2000. American Insects, A Handbook of the Insects of America
North of Mexico, 2nd edition, CRC Press, Boca Raton, FL. 1003 pp.
BugGuide 2013. “Hoplistoscelis heidemanni.” Available at:
http://bugguide.net/node/view/296746/bgimage (Accessed 11 March 2013).
Elvin, M.K. and P.E. Sloderbeck 1984. A key to the nymphs of selected species
of Nabidae (Hemiptera) in the southeastern USA. Fla. Entomol. 67: 269-273.
Harris, H.M. 1928. A monographic study of the Hemipterous family Nabidae as
it occurs in North America. Entomologica Americana 9: 1-97.
Henry, T.J. 2009. Biodiversity of Heteroptera. Chapter 10. Pp. 223–263 In:
Foottit, R.G.; Adler, P.H. (eds) 2009: Insect Biodiversity: Science and Society.
Wiley-Backwell, Oxford, U.K. 656 pp.
Henry, T.J. and J. Brambila. 2003. First report of the neotropical damsel bug
Alloeorhynchus trimacula (Stein) in the United States, with new records for two
other nabid species in Florida (Heteroptera: Nabidae: Prostemmatinae).
Proceedings of the Entomological Society of Washington 105: 801-808.
Henry, T.J. and J.D. Lattin. 1988. Family Nabidae Costa. 1853. The damsel
bugs, pp. 508-520. In Henry. T. J. and R. C. Froeschner. eds. Catalog of the
Heteroptera, or true bugs, of Canada and the continental United States. E.J.
Brill, Leiden and New York. 958 pp.
Kerzhner, I.M. & T.J. Henry. 2008. Three new species, notes and new records
of poorly known species, and an updated checklist for the North American
Nabidae. Proceedings of the Entomological Society of Washington 110(4): 988–
1011.
Lattin, J.D. 1989. Bionomics of Nabidae. Annual Review of Entomology 34:
383–400.
6
Maw, H.E.L., Foottit, R.G., Hamilton, K.G.A. and G.G.F. Scudder. 2000.
Checklist of the Hemiptera of Canada and Alaska. NRC Research Press.
Ottawa, Ontario. 220 pp.
NatureServe. 2013. “Hoplistoscelis heidemanni.” NatureServe Explorer: An
online encyclopedia of life [web application]. Feb. 2009. Version 7.1.
NatureServe, Arlington, Virginia. Data last updated: October 2012. Available at:
www.natureserve.org/explorer (Accessed 11 March 2013).
Oregon State University Arthropod Collection (OSAC). 2013. Specimen data
gathered by Ashley Clayton, contractor for the Xerces Society.
Plagens, M.J. and W.H. Whitcomb. 1986. Corn residue as an overwintering site
for spiders and predaceous insects in Florida. The Florida Entomologist 69(4):
665-671.
Reuter, O.M. 1908. Bemerkungen über Nabiden nebst Beschreibung neuer
Arten. Mém. Soc. Entomol. Belg. Vol. 15 pp. 87-130.
Scudder, G.G.E. 1994. An annotated systematic list of the potentially rare and
endangered freshwater and terrestrial invertebrates in British Columbia.
Entomological Society of British Columbia, Occasional Paper 2: 1-92.
Scudder, G.G.E. 1996. Terrestrial and freshwater invertebrates of British
Columbia: priorities for inventory and descriptive research. Res. Br., B.C. Min.
For., and Wildl. Br., B.C. Min. Environ., Lands and Parks. Victoria, B.C. Work.
Pap. 09/1996.
Triplehorn, C. and N. Johnson. 2005. Introduction to the Study of Insects.
Thomson Brooks/Cole, Belmont, CA. 864pp.
United States National Museum (USNM). 2013. Statement by Thomas Henry
regarding USNM collection holdings of Hoplistoscelis heidemanni. Available at:
http://bugguide.net/node/view/296746/bgimage (Accessed 11 March 2013).
ATTACHMENT 2:
List of pertinent or knowledgeable contacts
Thomas Henry, Research Entomologist, Smithsonian National Museum of
Natural History, Washington DC.
John D. Lattin, Professor Emeritus, Oregon State University, Corvallis, Oregon.
Michael Schwartz, Research Affiliate, Insect Biosystematics, Canadian National
Collection of Insects.
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ATTACHMENT 3:
Maps of known records in Oregon
Known records of Hoplistoscelis heidemanni in Oregon, relative to BLM and
Forest Service lands.
8
Known record of Hoplistoscelis heidemanni at Humbug Mountain, relative to
BLM and Forest Service lands.
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ATTACHMENT 4:
Photograph of this species & illustration of relative
Hoplistoscelis heidemanni brachypterous (short-winged) adult female, as
indicated by the fully developed ovipositor (not apparent in photo) (Marshall
2013, pers. comm.). Photograph by Ashley Clayton for The Xerces Society, used
with permission. A photograph of the macropterous adult is available on
BugGuide.net (http://bugguide.net/node/view/296746#631950, accessed
March 2013).
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First through fourth nymphal instars of the related Hoplistocelis sericans.
Illustration from Elvin & Sloderbeck (1984). Note the wide (pear-shaped) body.
ATTACHMENT 5:
Survey Protocol for this species
Survey Protocol:
Hoplistoscelis heidemanni
Where:
This species is known from very few collections in Oregon, probably due (at
least in part) to limited sampling effort. Further surveys are needed for this
species in Oregon, and will be critical in evaluating its current status and
habitat use in the region. Initial surveys are recommended on BLM and Forest
Service land in the vicinity of the known Humbug Mountain site where this
species was last collected 1965.
Oregon surveys for this species should target forest riparian areas and skunk
cabbage (Lysichiton americanus) swales (Applegarth 1995). The habitat at the
Humbug Mountain site was described as a stream bank (Applegarth 1995). The
habitat at the Corvallis site is unknown. In Idaho, this species has been
collected from “yellow pine”, and in Arizona, from Ceanothus, a genus of shrubs
in the family Rhamnaceae (OSAC 2013).
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In Eastern North America, the related H. sericans has been found under bark
of a dead tree (BugGuide 2013). The related H. pallescens has been found
visiting flowers, under leaf litter in a flower bed, on the top surface of leaves,
and preying on adult flies (BugGuide 2013). Both H. pallescens and H. sericans
have been found at lights (BugGuide 2013).
When:
Surveys for this species are recommended in summer, although the phenology
of this species is poorly known. According to Applegarth (1995), specimens
have been found in early spring and late summer, although both of the recently
recovered Oregon specimens were collected in August (OSAC 2013). This
species has been collected in June and October in California (BugGuide 2013,
OSAC 2013), July and October in Idaho, and July in Arizona (OSAC 2013).
Nabids tend to overwinter as adults (Applegarth 1995).
How:
Since this species is known from very few collections in a variety of habitats,
survey methodologies are difficult to develop. Visual searches and sweepnetting in known habitat (forest riparian areas and skunk cabbage swales) are
probably the most appropriate survey method to employ at this time. It is
unclear if this species has been collected from skunk cabbage, or simply in
skunk cabbage habitat, but in case of the former, visual searches should target
skunk cabbage leaves, including leaf surfaces and spaces between the leaf
sheaths. Surveyors may also wish to target yellow pine (or other Pinus species)
and Ceanothus shrubs, since H. heidemanni has been collected from these
plants outside of Oregon (OSAC 2013). Given the scarcity of habitat
information for this species, surveyors may also wish to target microhabitats
where other members of this genus have been collected, including leaf surfaces,
leaf sheaths, flowers, leaf litter and under bark (OSAC 2013, BugGuide 2013,
Plagens & Whitcomb 1986). Both H. pallescens and H. sericans are known to
come to visible light (e.g., porch lights) (BugGuide 2013). It is unclear if
Hoplistoscelis species are attracted to ultraviolet (UV) light, but Blinn (1995)
reports the use of UV light traps to collect another member of this family
(Phorticus collaris).
After capture, voucher specimens should be placed immediately into a kill jar
until they can be pinned. A field catch can also be temporarily or permanently
stored in 75% ethyl alcohol but the alcohol will cause some colors to fade
(Triplehorn & Johnson 2005). Adult specimens should be pinned through the
scutellum (Triplehorn & Johnson 2005). Juveniles are best preserved in vials
containing 75% ethyl alcohol. Collection labels should include the following
information: date, collector, detailed locality (including geographical
coordinates, mileage from named location, elevation, etc.), and detailed
habitat/host plant. Complete determination labels include the species name,
sex (if known), determiner name, and date determined.
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Field identification is possible by those familiar with heteropteran taxonomy,
and can be accomplished by non-experts who have examined and become
familiar with museum specimens. This species is identified using
characteristics provided in the Species Fact Sheet. Confirmation of field
identifications should be done by taxonomic experts with experience identifying
nabids.
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